/Engine/Source/Runtime/MessagingCommon/Public/MessageEndpoint.h
The message is effectively delivered again to this endpoint after the original sent time plus the time delay have elapsed.
void Defer ( const [TSharedRef](API\Runtime\Core\Templates\TSharedRef)< [IMessageContext](API\Runtime\Messaging\IMessageContext), ESPMode::ThreadSafe > & Context, const [FTimespan](API\Runtime\Core\Misc\FTimespan) & Delay )